Fig. 6

erbb2 receptor is required in neurons, but not oligodendrocytes, for normal myelination in the spinal cord

(A) Confocal images show that claudink:GFP-labeled oligodendrocytes (OL) in erbb2 mutants generate less myelin than wild-type controls. Scale bars, 20 μm.

(B) Quantification of myelin produced by individual OLs in animals wild-type, heterozygous, or mutant for erbb2^st61. OLs in animals lacking erbb2 produce significantly less myelin. Each point represents one OL; at least 40 OLs analyzed from ≥6 animals per genotype; one representative experiment shown from three replicates. Animals were genotyped after imaging.

(C) Diagram of cell type-specific CRISPR construct design, allowing expression of Cas9 in OLs (claudin), all neurons (NBT), or RBs (LSEC), and ubiquitous expression of erbb2-targeted sgRNA.

(D) Confocal images of oligodendrocytes in the dorsal spinal cord labeled using the claudink:GFP transgene. Dotted circle indicates the OL cell body, while brackets indicate the breadth of a single OL.

(E) erbb2 cell type-specific CRISPR quantification. Total myelin sheath length produced by individual oligodendrocytes in animals expressing Cas9 in neurons is significantly less than in the other conditions. No significant change in myelin production occurred in animals with erbb2 knockdown in RB neurons or oligodendrocytes. Each point represents one OL; at least 15 OLs quantified from ≥4 animals per category; one representative experiment shown from three replicates. Error bars represent mean ± SD. A t test was used to assess significance, and p values were adjusted for multiple comparisons. See also Figures S5 and S7.